On Tue, 6 Aug 2002, Mark Hahn wrote:
> > Especially crippled on-board LAN interfaces (i.e. the drivers don't work,
> > it's badly implemented, no possibility for booting over LAN, etc.)
>> RTL 8193's might qualify for that, though they're not really crippled,
> just less featureful/efficient than others. I have no idea whether the
> RTL (9xxx?) I see bundled on some boards is similar.
There are various numbers for the on-motherboard rtl8139C chips. A
common number is 8130, which is very similar to the 8139.
The rtl8139 is one of the least effective Fast Ethernet chips. Packets
usually have to be copied on transmit, and always must be copied on
receive.
When the 8139C+ (the "+" is the important part) becomes common, the
situation will completely change. The C+ design implements full
descriptors, IP checksumming, and TCP transmit offload (!). In most
situations TCP Tx offload is marginally useful, but it could be very
useful with stream transfers in clusters.
> > Chipsets that are just so oriented towards consumer apps that they choke
> > the memory, or require some exotic (expensive) configuration, or
> > have weird video card interactions,
>> wow, never even heard of such a thing. choke memory? the only video
> card interactions I've heard of are broken video cards that don't
> play nice with the bus...
>> > or are totally undocumented in the "open literature"
>> haven't they all caved to the onslaught of the penguin army?
The situation isn't any better now than five years ago...
--
Donald Becker becker at scyld.com
Scyld Computing Corporation http://www.scyld.com
410 Severn Ave. Suite 210 Second Generation Beowulf Clusters
Annapolis MD 21403 410-990-9993